CN1891680B - Process for producing high purity, halogen-free o-phthalaldehyde - Google Patents

Process for producing high purity, halogen-free o-phthalaldehyde Download PDF

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CN1891680B
CN1891680B CN200610090517XA CN200610090517A CN1891680B CN 1891680 B CN1891680 B CN 1891680B CN 200610090517X A CN200610090517X A CN 200610090517XA CN 200610090517 A CN200610090517 A CN 200610090517A CN 1891680 B CN1891680 B CN 1891680B
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phthalaldehyde
opa
halogen
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CN1891680A (en
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卡尔海因兹·吉斯埃尔布利楚特
克劳斯·雷特尔
鲁道夫·赫尔曼瑟德
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DPx precision chemical Austria Limited by Share Ltd.
ESIM chemical Limited by Share Ltd.
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DSM Fine Chemicals Austria Nfg GmbH and Co KG
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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C47/00—Compounds having —CHO groups
    • C07C47/52—Compounds having —CHO groups bound to carbon atoms of six—membered aromatic rings
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C41/00—Preparation of ethers; Preparation of compounds having groups, groups or groups
    • C07C41/48—Preparation of compounds having groups
    • C07C41/50—Preparation of compounds having groups by reactions producing groups
    • C07C41/56—Preparation of compounds having groups by reactions producing groups by condensation of aldehydes, paraformaldehyde, or ketones
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
    • C07C45/42—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by hydrolysis
    • C07C45/43—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by hydrolysis of >CX2 groups, X being halogen
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
    • C07C45/51—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by pyrolysis, rearrangement or decomposition
    • C07C45/511—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by pyrolysis, rearrangement or decomposition involving transformation of singly bound oxygen functional groups to >C = O groups
    • C07C45/515—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by pyrolysis, rearrangement or decomposition involving transformation of singly bound oxygen functional groups to >C = O groups the singly bound functional group being an acetalised, ketalised hemi-acetalised, or hemi-ketalised hydroxyl group
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
    • C07C45/78—Separation; Purification; Stabilisation; Use of additives
    • C07C45/81—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
    • C07C45/78—Separation; Purification; Stabilisation; Use of additives
    • C07C45/85—Separation; Purification; Stabilisation; Use of additives by treatment giving rise to a chemical modification
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T436/00—Chemistry: analytical and immunological testing
    • Y10T436/20—Oxygen containing
    • Y10T436/200833—Carbonyl, ether, aldehyde or ketone containing

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  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)

Abstract

Provided an improved method for producing high-purity halogen-free o-phthalaldehyde. This method for producing the high-purity halogen-free o-phthalaldehyde comprises (a) hydrolyzing a tetrahalo-o-xylene at a temperature of 155-160[deg.]C and a pressure of 2-5 bar and, when necessary, in the presence of a phase transition catalyst, so as to form o-phthalaldehyde, then (b) converting the o-phthalaldehyde into a dialkoxyphthalan corresponding thereto in an acidic alcohol solvent having a temperature of 0[deg.]C to a reflux temperature, and further (c) acetalizing the dialkoxyphthalan by acidic hydrolysis at a pH of more than 1.5 to a pH of 7.

Description

The method for preparing highly purified halogen-free o-phthalaldehyde
For example the phthalaldehyde of Phthalyldicarboxaldehyde (OPA) can be used for a lot of fields, for example can be used as the intermediate of dyestuff, optical brightener or particular polymers, can be used for biotic pesticide or photograph industry, and is used for synthetic drug.Of many uses because of it, existing description to several different methods.Therefore, for example according to EP-B-0147593, Phthalyldicarboxaldehyde (OPA) can obtain by the following method: in methyl alcohol naphthalene is carried out ozone and decompose, and the superoxide that generates is carried out catalytic reduction, extract then or crystallization.The shortcoming of this method is to be difficult to formed ester as by product is separated with OPA, and separates also insufficient.
In addition, OPA is to heat and the unsettled reactive compounds of oxidation, and prolonged storage then is easy to caking, thereby makes the dissolution process required time longer, and this can cause the OPA decolouring.A kind of possible method that prevents the reaction that the aldehyde generation is not expected has been described: use the Phthalyldicarboxaldehyde tetraalkyl acetal for preparing by electrochemical oxidation among the EP-A1-0522312 as the storage compound.
EP-B-0839789 further discloses and has formed acetal by acid catalysis and distill subsequently OPA is changed into suitable storage compound, for example be converted into dialkoxyphthalan (dialkoxyphthalane) or tetraalkyl acetal, after acetal being decomposed fully, can obtain purity and surpass 99.5% thick OPA by acid hydrolysis.
Yet for example the thick OPA according to the EP-B-0839789 preparation is orange, also need carry out recrystallization again after with for example activated carbon or Tonsil decolouring.
The fusing point that obtains by crystallization is that 57 ℃ thin OPA powder is easy to into piece equally.And the shade and quality of different products in batches also there are differences.
US 5107032 discloses by the preparation tetrahalo-o-xylene and has prepared OPA 90-146 ℃ of following hydrolysis subsequently.This need come for example tetrachloro-o-Xylol of hydrolysis with sodium acetate in acetic acid aqueous solution under the highest 146 ℃ and 3.5bar, afterwards with toluene extraction 5 times, the organic phase that merges of distillation then obtains yield and be 87% OPA.But it is not halogen-containing that one of shortcoming of this method is that products obtained therefrom is not.
Therefore, the objective of the invention is to find improving one's methods of the highly purified Halogen OPA of preparation.
Unexpectedly, this purpose realizes by the following method: hydrolysis tetrahalo-o-xylene under greater than 155 ℃ high temperature, acetal turns to corresponding Phthalyldicarboxaldehyde acetal afterwards, comes the purifying acetal by distillation, decomposes acetal at pH under greater than 1.5 condition then.
Therefore, the present invention relates to prepare improving one's methods of highly purified halogen-free o-phthalaldehyde, it comprises:
A) under the pressure of 155-160 ℃ temperature and 2-5bar, suitably in the presence of phase-transfer catalyst, tetrahalo-o-xylene is hydrolyzed into Phthalyldicarboxaldehyde,
B) 0 to the temperature of reflux temperature, in acidity alcohol solution, Phthalyldicarboxaldehyde is converted into corresponding dialkoxyphthalan, then
C) under greater than 1.5 to 7 pH, by acid hydrolysis so that acetal decomposition obtains highly purified halogen-free o-phthalaldehyde.
Method of the present invention can prepare highly purified halogen-free o-phthalaldehyde.
Initiator is a tetrahalo-o-xylene.Suitable tetrahalo-o-xylene is the compound of following formula for example:
Figure A20061009051700041
Wherein, X can be Cl, Br or I
Tetrahalo-o-xylene (THX) can also be replaced once or more times by suitable base alternatively.The example of suitable base is C 1-C 4Alkyl, C 5-C 20Aryl, OH, NO 2, CN, Cl, Br or CO 2H.The unsubstituted THX compound of preferred use, and X is preferably chlorine.Suitable THX compound can be buied (wherein X is Cl or Br) maybe can be with known method preparation, for example by under conditions of exposure or by means of for example AIBN, PCl 3Make o-Xylol and chlorine element reaction with the radical initiator of dibenzoyl peroxide etc.
According to the present invention, under the pressure of 155-160 ℃ temperature and the preferred 3-4bar of 2-5bar, THX is hydrolyzed to corresponding Phthalyldicarboxaldehyde.In the presence of alkali (for example NaOH, LiOH, KOH etc.), hydrolysis is by C 1-C 4Carry out in the Aquo System that carboxylic acid is formed.Preferably in the presence of NaOH (intensity 40-50%), use acetate.For this purpose, preferably carboxylic acid or moisture carboxylic acid are mixed with THX, add aqueous alkali and water then.Yet the order of interpolation also can change.The amount of used carboxylic acid is greater than 4 to 20 molar equivalents based on THX.Being preferably based on THX is the 8-10 molar equivalent.The amount of used alkali is the 4.0-5.0 molar equivalent based on THX.
In order to reach higher speed of reaction, can suitably in reaction mixture, add phase-transfer catalyst (PTC) (is 1-5mol% based on THX).Suitable PTC is that conventional for example quaternary ammonium salt is with the compound of quaternary alkylphosphonium salt, for example tetraalkylammonium salt and Si Wan Ji phosphonium salt or aralkyl trialkyl ammonium salts.Preferred salt is halide salt.Its example is tetrabutylammonium chloride or Tetrabutyl amonium bromide, ethyl trioctylphosphine phosphonium chloride, benzyltriethylammoinium chloride etc.
After hydrolysis takes place, obtain corresponding thick Phthalyldicarboxaldehyde (OPA), then solvent and extraction agent are distilled by extracting with for example conventional extraction agent of methyl tertiary butyl ether, toluene, ethyl acetate etc.
Subsequently, in step b),, in a usual manner thick OPA is changed into acetal, i.e. dialkoxyphthalan by carrying out the acid catalysis acetalation with alcohol.In the case, the alcohol of use is preferably C 1-C 4Alcohol, special particular methanol or ethanol.For this purpose, thick OPA is dissolved in alcohol.Transfer to 0-3, preferred 0.5-2 by adding sour pH then with solution.The example of suitable acid is for example HCl, H 2SO 4, H 3PO 4The organic acid or the acid ion exchangers of mineral acid, for example formic acid, acetate, tosic acid or methylsulfonic acid.The temperature of this step be 0 ℃ to reflux temperature, preferred 0 ℃ to 50 ℃.
After acetalation takes place, in solution, add aqueous alkali with neutralizing acid or acidic organic compound.The example of suitable alkali is NaOH or KOH.
Subsequently or simultaneously, remove alcohol by distillation as solvent.
Then, dialkoxyphthalan is separated with subsequently distillation by extraction.At this moment, the isolating OPA acetal of gained has high Halogen quality (＞99.5GC area %) and very high yield (greater than 92%).
In step c), be similar to prior art, the decomposition of acetal takes place equally in a conventional manner by acid hydrolysis.According to the present invention, pH is greater than 1.5 to 7, preferred 1.6-2.5.
Used acid is similarly for example HCl, H 2SO 4, H 3PO 4The mineral acid or the organic acid of acetate, formic acid and tosic acid or methylsulfonic acid for example.Temperature of reaction is preferably between room temperature and 60 ℃.Pure and mild (in appropriate circumstances) acid of removing simultaneously, is steamed.Then, in appropriate circumstances, the OPA that obtains in this way can for example be further purified by extraction, washing or crystallization.
OPA by purification process gained of the present invention has high Halogen quality (＞99.5GC area %) and very high yield (greater than 92%).And, come the OPA of purifying to present the fixed color according to the present invention, no longer need to decolour with Tonsil or carbon.In addition, method of the present invention has also been avoided the loss of OPA yield.
Compared with prior art, the feature of method of the present invention also is to have shortened the reaction times, thereby makes continuous processing become possibility.
Embodiment 1
Step a):
61g (0.25mol) tetrachloro-o-Xylol (TCX) (purity 99%) is introduced reactor, add 300g (5mol) acetate then.Slowly add the solution of 44g (1.1mol) NaOH and 198g deionized water afterwards.Reacting by heating mixture to 160 ℃, and keep this temperature 1h.Reaction pressure is 3.8-3.9bar.Then, reaction mixture is cooled to 40 ℃, and shifts out reactor (obtaining 606g (525mi) reaction soln).Get the 2ml sample, and it is analyzed.Analytical results: the thick OPA of 99.43GC area %.
Extract thick OPA:
At first the thick OPA solution of 606g is mixed with the 50ml deionized water, then with 93g MTBE extraction 4 times.Merge organic phase, under 400-415mbar and 34-72 ℃, in Rotavapor, concentrate then, pass through until no longer including fraction.Obtain the 54g residuum by evaporation.
Step b):
With the whole residuums and the 375ml methanol mixed of evaporation gained, add the dense H of 2ml 2SO 4So that pH is transferred to 0.5.After keeping 2 hours under 50 ℃, add the NaOH of 50% intensity of 10ml.Then reaction mixture is concentrated in Rotavapor, mix with the 175ml deionized water afterwards, and extract 3 times with 80ml MTBE down at 25 ℃.Merge organic phase, in Rotavapor, concentrate.Final weight is 42.4g.
It is 135-140 ℃ that thick acetal is carried out the distillatory bath temperature, and bottom temp is 113-114 ℃, and head temperature is 110-111 ℃.Pressure is 8-10mbar.Final weight: 41.2g OPA dimethoxy acetal (theoretical yield 91%).
Step c): decompose OPA dimethoxy acetal
200g OPA dimethoxy acetal is added in the 500g deionized water, and described deionized water is regulated pH to 2.0 with sulfuric acid, and pressure is reduced to about 150mbar.Begin heating then.When bottom temp is 53 ℃, when pressure is 155mbar, begins to collect fraction.Obtain the 270ml fraction altogether.Behind the 4h organic phase is carried out IPC-GC and analyze, show that OPA purity is 99.89 area %.
Add after the 500ml DIPE, extract OPA down at 50 ℃.After being separated, (each 100ml) washs organic phase 2 times with deionized water.With the light yellow organic solution reflux of having washed, under barometric point, remove residual water in the organic phase by component distillation.Obtain the water of 9.5ml altogether.
Subsequently, begin slowly to cool off.Under 42 ℃, OPA begins crystallization.Further it is cooled to 15 ℃.
By G-2frit crystalline OPA is leached, with 150ml DIPE washing and under 40-45 ℃ dry overnight in a vacuum.91.5g content is separated greater than 99.8% dry OPA and 450ml mother liquor.Theoretical yield is 61.5%.In the water and the water from washing that theoretical yield according to 100%, remaining OPA be present in mother liquor, obtained by decomposition, because the high purity and the light colour of solution, all these all can recycling in next acetal decomposition is handled.Therefore make quantitative acetal decomposition become possibility.

Claims (5)

1. preparation purity is greater than the method for the halogen-free o-phthalaldehyde of 99.5 GC area %, and it comprises:
A) under the pressure of 155-160 ℃ temperature and 2-5bar, tetrahalo-o-xylene is hydrolyzed to Phthalyldicarboxaldehyde,
B) 0 to the temperature of reflux temperature, in acidity alcohol solution, described Phthalyldicarboxaldehyde is converted into corresponding dialkoxyphthalan, then
C) under greater than 1.5 to 7 pH, by acid hydrolysis so that acetal decomposition obtains the halogen-free o-phthalaldehyde of purity greater than 99.5 GC area %,
Wherein, described tetrahalo-o-xylene is the compound of formula (I):
Figure FSB00000568381400011
Wherein, X is Cl, Br or I;
And wherein, described step a) is in the presence of alkali and water, at C 1-C 4Carry out in the carboxylic acid.
2. method as claimed in claim 1, wherein said step a) is carried out in the presence of phase-transfer catalyst.
3. method as claimed in claim 1, the consumption of wherein said carboxylic acid is to 20 molar equivalents more than 4 molar equivalents based on tetrahalo-o-xylene.
4. method as claimed in claim 1, wherein said step b) are to take place under the pH between 0 and 3.
5. method as claimed in claim 1, wherein said step c) are to take place under the pH between 1.6 and 2.5.
CN200610090517XA 2005-06-28 2006-06-27 Process for producing high purity, halogen-free o-phthalaldehyde Active CN1891680B (en)

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JP4024554B2 (en) * 2001-02-27 2007-12-19 松下電器産業株式会社 Fuel cell power generation system
JP5733055B2 (en) * 2011-06-29 2015-06-10 住友化学株式会社 Method for producing 2- (aryloxymethyl) benzaldehyde compound
CN104621104A (en) * 2015-02-02 2015-05-20 山东威高药业股份有限公司 Disinfectant with low corrosiveness

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CN1181369A (en) * 1996-10-30 1998-05-13 Dsm林茨化学有限公司 Process for purification of O-phthalaldehyde

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DE2860613D1 (en) * 1977-12-30 1981-04-30 Ciba Geigy Ag Process for the preparation of o-phthalic aldehydes optionally having several substituents
DE3108790A1 (en) * 1981-03-07 1982-09-16 Dynamit Nobel Ag, 5210 Troisdorf Process for the preparation of bis(dialkoxymethyl)benzenes
SE8102761L (en) * 1981-05-04 1982-11-05 Eka Ab METHOD AND APPARATUS FOR HYDROLYSIS OF ALFA-CHLORATED TOLUEN COMPOUNDS
US5107032A (en) * 1990-11-20 1992-04-21 Noramco, Inc. Process for the preparation of o-phthalaldehydes
DE4122314A1 (en) * 1991-07-05 1993-01-07 Basf Ag O-PHTHALDIALDEHYDTETRAALKYLACETALES, THEIR PREPARATION AND THEIR USE AS DEPOT CONNECTIONS
JPH08245478A (en) * 1995-03-14 1996-09-24 Konica Corp Production of aromatic aldehydes

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1181369A (en) * 1996-10-30 1998-05-13 Dsm林茨化学有限公司 Process for purification of O-phthalaldehyde

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Title
吴立昌、张世红、蔡巍.邻苯二甲醛的合成新工艺.黑龙江医药.1998,11(1),6. *

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CN1891680A (en) 2007-01-10
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US7858381B2 (en) 2010-12-28
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JP5128787B2 (en) 2013-01-23
NO337154B1 (en) 2016-02-01
US20060293542A1 (en) 2006-12-28
ES2329274T3 (en) 2009-11-24
EP1741695B1 (en) 2009-07-15
IL176512A0 (en) 2006-10-05
CA2550638A1 (en) 2006-12-28
EP1741695A1 (en) 2007-01-10
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AT502144A1 (en) 2007-01-15
AU2006202718B2 (en) 2011-11-17

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